1. Field of the Invention
The distribution adapter disclosed herein is related to the distribution of signals in a telecommunications or a data network using twisted pair conductors. More particularly this adapter is intended to be used in connecting corresponding conductors in two twisted pair cables, such as twisted pairs in a twenty-five pair cable to a four-pair cable connected to an individual user station. More particularly, this invention is related to the interconnection of a cable including multiple conductors terminated to a multiposition connector such as a twenty-five pair (fifty position) miniature ribbon connector to standard connectors used with four-pair cable, such as modular jacks and punchdown blocks.
2. Description of the Prior Art
Twisted pair conductors are used to distribute signals in a wide variety of applications. The most common traditional use of twisted pair wires and cables is probably for the distribution of telephone signals where these cables are used for the distribution of POTS, analog voice and digital voice and these conductors are also used for ISDN communications. Four wire and six wire cables are commonly used in premise telephone systems to interconnect individual telephones and eight wire cables are used for ISDN applications. Twenty-five pair cables are used where it is necessary to run a large number of wire pairs between two points, for example to connect separate wiring closets in a commercial building. In such applications it is quite common to run twenty-five pair cables between wiring closets and then to connect smaller count cables between using patch panels in the wiring closets. Smaller count cables can then extend between the wiring closets and individual user equipment. Alternatively, twenty-five pair cables can extend from the wiring closets to distribution adapters where smaller count cables can be attached.
Twisted pair cables are also commonly used in local area networks for data communications. Different applications require different performance standards for the cable used in such applications and twisted pair cable classifications have been established for unshielded twisted pair cables by the Electronic Industries Association. For example, Category 1 cable are suitable for POTS, analog voice and digital voice. Category 2 is suitable for 1.44 Mbps ISDN and T1 while Category 3 is suitable for 10BASE-T. Categories 4 and 5 are intended for higher speed applications. For example Category 5 is intended for data rates on the order of 100 mbps.
Standard electrical connectors, such as modular jacks, punchdown blocks and twenty-five pair miniature ribbon connectors that are used in telephone applications are also suitable for many data communications applications, including Category 3 systems. The use of twenty-five pair cable and connectors for this cable is a common wiring technique and is effective for higher count cable runs, such as between wiring closets. There are however other applications, both in telecommunications applications and in data applications, in which higher count cables, such as twenty-five pair cables, can be effectively employed. For example, a breakout adapter or tap for connecting six (6) four-pair cables directly to a twenty-five pair cable can be useful in many applications.
There are a number of commercially available distribution adapters and distribution box assemblies available for such applications. AMP Incorporated manufactures and sells several distribution adapters, assemblies and boxes of this type. For example, AMP manufactures a Category 3 multi-jack adapter, AMP Part No. 553150-1, that includes two twenty-five pair connectors and five eight position modular jacks. In that adapter, male and female vertical mount twenty-five pair connectors are mounted on a printed circuit board and traces connect individual contacts to corresponding contacts in five vertical mount modular jacks located beside one of the twenty-five pair connectors. Mating twenty-five pair cable connectors can be attached to the printed circuit board mounted twenty-five pair connectors and modular plugs can be mated with the board mounted modular jacks. This adapter is suitable for either a star breakout or for tapping the wires in the twenty-five pair cable. This printed circuit board assembly and the cable connectors are housed in a box having a hinged cover. Since the cable connectors are also positioned in the box, the height of this box (1.922 in) is relatively large, and this adapter is suitable for standalone applications.
AMP Incorporated also manufactures a Category 3 Modular Distribution Box, AMP Part No. 555488-1, that has a lower profile (1.50 in.) in which right angle printed circuit board mounted twenty-five pair connectors are used. In this distribution box the cover includes slots so that mating twenty-five pair cable connectors can be attached to the board mounted twenty-five pair connectors on the side. The commercial version of this device includes two (2) twenty-five pair connectors and twelve (12) vertical mount modular jacks. Depending on the application an adapter of this type could include printed circuit board traces for breaking out four-pair cables from two individual twenty-five pair cables or the traces could connect corresponding positions between the two twenty-five pair board mounted connectors so that the modular jacks would provide a tap.
AMP Incorporated also manufactures and sells Category 3 twenty-five pair modular adapters that comprise a printed circuit board containing a right angle printed circuit board jack and vertical mount six or eight position modular jacks on the printed circuit board, AMP Part Nos. 553867 and 553868.
Although these commercially available adapters, assemblies, and distribution boxes permit taps or breakouts from twenty-five pair cables to four-pair cables or other lower count cables, these prior art devices do not provide sufficient versatility to meet all of the practical applications encountered in typical installations. For example, these breakouts or taps may be required in patch panels, in stand alone applications in which the special housing or boxes provided are suitable, in applications in which the tap or breakout would desirably be housed in other general purpose boxes, such as boxes normally used for power distribution, in undercarpet wiring installations, in plenums, in access floor applications, and in low profile access floor installations such as the POWERFLOR access floors manufactured and sold by Powerflor, Inc. of Charlotte, N.C. and disclosed in U.S. Pat. No. 5,392,571. For example, the overall height of a POWERFLOR pedestal module is 2 5/8 inches (6.7 cm.). No single distribution box or adapter assembly is suitable for all of these applications, primarily because of the dimensional constraints imposed by these applications. For example, the height and width of these commercially available assemblies are incompatible with low profile access floor applications. The distribution adapter of the present invention, however, is sufficiently versatile to be used in each of these applications. A single configuration will therefore meet all of these needs. The basic invention is also suitable to other applications that may use other standard connector configurations.
Unlike the Category 3 distribution adapters referred to previously, this invention is also suitable for higher speed applications including 100 mbps applications.